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	<head>
		<title>three.js webgl - buffer geometry custom attributes - particles</title>
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			body {
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				background-color: #000000;
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				position: absolute;
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				font-size: 13px;
				text-align: center;
				font-weight: bold;
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			a {
				color: #fff;
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		</style>
	</head>

	<body>
		<div id="container"></div>
		<div id="info"><a href="http://threejs.org" target="_blank">three.js</a> webgl - buffergeometry custom attributes - particles</div>

		<script src="../build/three.js"></script>

		<script src="js/Detector.js"></script>
		<script src="js/libs/stats.min.js"></script>

		<script type="x-shader/x-vertex" id="vertexshader">

			attribute float size;
			attribute vec3 customColor;

			varying vec3 vColor;

			void main() {

				vColor = customColor;

				vec4 mvPosition = modelViewMatrix * vec4( position, 1.0 );

				gl_PointSize = size * ( 300.0 / -mvPosition.z );

				gl_Position = projectionMatrix * mvPosition;

			}

		</script>

		<script type="x-shader/x-fragment" id="fragmentshader">

			uniform vec3 color;
			uniform sampler2D texture;

			varying vec3 vColor;

			void main() {

				gl_FragColor = vec4( color * vColor, 1.0 );

				gl_FragColor = gl_FragColor * texture2D( texture, gl_PointCoord );

			}

		</script>


		<script>

		if ( ! Detector.webgl ) Detector.addGetWebGLMessage();

		var renderer, scene, camera, stats;

		var particleSystem, uniforms, geometry;

		var particles = 100000;

		var WIDTH = window.innerWidth;
		var HEIGHT = window.innerHeight;

		init();
		animate();

		function init() {

			camera = new THREE.PerspectiveCamera( 40, WIDTH / HEIGHT, 1, 10000 );
			camera.position.z = 300;

			scene = new THREE.Scene();

			uniforms = {

				color:     { value: new THREE.Color( 0xffffff ) },
				texture:   { value: new THREE.TextureLoader().load( "textures/sprites/spark1.png" ) }

			};

			var shaderMaterial = new THREE.ShaderMaterial( {

				uniforms:       uniforms,
				vertexShader:   document.getElementById( 'vertexshader' ).textContent,
				fragmentShader: document.getElementById( 'fragmentshader' ).textContent,

				blending:       THREE.AdditiveBlending,
				depthTest:      false,
				transparent:    true

			});


			var radius = 200;

			geometry = new THREE.BufferGeometry();

			var positions = new Float32Array( particles * 3 );
			var colors = new Float32Array( particles * 3 );
			var sizes = new Float32Array( particles );

			var color = new THREE.Color();

			for ( var i = 0, i3 = 0; i < particles; i ++, i3 += 3 ) {

				positions[ i3 + 0 ] = ( Math.random() * 2 - 1 ) * radius;
				positions[ i3 + 1 ] = ( Math.random() * 2 - 1 ) * radius;
				positions[ i3 + 2 ] = ( Math.random() * 2 - 1 ) * radius;

				color.setHSL( i / particles, 1.0, 0.5 );

				colors[ i3 + 0 ] = color.r;
				colors[ i3 + 1 ] = color.g;
				colors[ i3 + 2 ] = color.b;

				sizes[ i ] = 20;

			}

			geometry.addAttribute( 'position', new THREE.BufferAttribute( positions, 3 ) );
			geometry.addAttribute( 'customColor', new THREE.BufferAttribute( colors, 3 ) );
			geometry.addAttribute( 'size', new THREE.BufferAttribute( sizes, 1 ) );

			particleSystem = new THREE.Points( geometry, shaderMaterial );

			scene.add( particleSystem );

			renderer = new THREE.WebGLRenderer();
			renderer.setPixelRatio( window.devicePixelRatio );
			renderer.setSize( WIDTH, HEIGHT );

			var container = document.getElementById( 'container' );
			container.appendChild( renderer.domElement );

			stats = new Stats();
			container.appendChild( stats.dom );

			//

			window.addEventListener( 'resize', onWindowResize, false );

		}

		function onWindowResize() {

			camera.aspect = window.innerWidth / window.innerHeight;
			camera.updateProjectionMatrix();

			renderer.setSize( window.innerWidth, window.innerHeight );

		}

		function animate() {

			requestAnimationFrame( animate );

			render();
			stats.update();

		}

		function render() {

			var time = Date.now() * 0.005;

			particleSystem.rotation.z = 0.01 * time;

			var sizes = geometry.attributes.size.array;

			for ( var i = 0; i < particles; i++ ) {

				sizes[ i ] = 10 * ( 1 + Math.sin( 0.1 * i + time ) );

			}

			geometry.attributes.size.needsUpdate = true;

			renderer.render( scene, camera );

		}

	</script>

</body>
</html>
